Amide-epoxide compositions



United States Patent O US. Cl. 260836 9 Claims ABSTRACT OF THE DISCLOSURE Novel crossliukable compositions are prepared by combining an interpolymer having pendant carboxamide and/ or sulfonamide groups with a polyepoxide having more than one oxirane group per molecule. The interpolymers may contain from 15 to 30% by weight of pendant carboxamide, as exemplified by vinyl aromatic sulfonamides, vinyl aliphatic sulfonamides, acrylamide and methacrylamide. In an example 10 g. of a solution of a copolymer of 30% acrylamide and 70% butyl acrylate were reacted with a stoichiometric amount of an epoxide, e.g. 0.89 g. of vinyl cyclohexene dioxide.

CROSS REFERENCE This application is a continuation-in-part of our copending application Ser. No. 423,855 filed on J an. 6, 1965' now abandoned.

BACKGROUND OF THE INVENTION This invention relates to thermosettable amide-epoxide resin compositions which comprise a polyepoxide resin having more than one oxirane group per molecule and an interpolymer having pendant amide groups wherein said amide groups are derived from a carboxamide monomer and/or a sulfonamide monomer, and a process of making the same.

US. Patent 2,589,245, describes resinous amide-epoxide compositions comprising insoluble, infusible products. US. Patent 2,712,001 describes resinous sulfonamideepoxide compositions that are insoluble infusible products.

SUMMARY OF THE INVENTION The present invention is directed towards crosslinkable amide-epoxide compositions. More particularly the compositions comprise (a) a polyepoxide resin having more than one oxirane group per molecule and (b) an interpolymer having pendant amide groups obtained by polymerizing from about to about 30 percent by weight of a carboxamide monomer, a sulfonamide monomer or mixtures thereof with about 85 to about 70 percent by weight of at least one other copolymerizable monomer having no epoxide reactive sites. The cured compositions exhibit marked chemical resistance and possess excellent physical properties.

DETAILED DESCRIPTION Amide monomers useful in preparing the inter-polymers of this invention are carboxamide and/or sulfonamide monomers. Suitable carboxamides include acrylamide, methacrylamide and the like. Said sulfonamide monomers include vinyl aliphatic sulfonamides, vinyl aromatic monoand disulfonamides and the like. Suitable aromatic sulfonamide monomers include vinylbenzene sulfonamide, vinyltoluene sulfonamide, vinylnaphthalene sulfonamide, vinylbenzene disulfonamide, the isomers thereof and the like. Aliphatic sulfonamides include ethenesulfonamide, allylsulfonamide and various substituted derivatives thereof which have a terminal vinylidene group.

Patented Mar. 17, 1970 "ice wherein X and Y each represent a member of the group consisting of hydrogen, halogen and alkyl radicals having from 1 to 4 carbon atoms; acrylate esters having the general formula 0 ngo o-iz-o-n,

wherein R is hydrogen or methyl and R is an alkyl radical having from 1 to 8 carbon atoms; acrylonitrile and methacrylonitrile; vinyl ethers; maleate esters; vinyl pyrrolidone, N-vinyl-5-methyl-2-oxazolidinone and the like;

' vinyl acetate; and the like.

Examples of said polymerizable monomers include styrene, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, butyl methacrylate, vinyltoluene, isopropylstyrene, vinylxylene, chlorostyrene, dichlorostyrene, tert.-butylstyrene and the like.

The interpolymer can be prepared by the solution polymerization of the carboxamide monomer or the sulfonamide monomer in amounts of from 15 to 30 percent by weight in admixture with from to 70 percent by weight of the copolymerizable monomer having no epoxide reactive sites.

Polyepoxides useful for the present invention comprise all aromatic and aliphatic polyepoxides commercially available. Preferably, the polyepoxides are glycidyl polyethers of polyhydric alcohols or phenols and contain more than one oxirane group per molecule.

Polyepoxides useful in making the novel compositions are m-diisopropenyl benzene diepoxide, divinyl benzene diepoxide, 3,4 epoxy 6-methyl cyclohexyl methyl-3,4- epoxy 6 methyl cyclohexane carboxylate, vinylcyclohexene dioxide, dicyclopentadiene diepoxide, dipentene dioxide, diglycidyl ether of 2,2-bis(4-hydroxyphenyl)-pro pane, the diglycidyl ether of polypropylene glycol, epoxy novolacs, the various halogen containing polyepoxides, and the like.

The amount of the polyepoxide employed can be varied from about 0.1 equivalent of epoxide per amide group of I the interpolymer to more than two equivalents per amide group. The proportions are dependent on the percentage of the amide in the interpolymer, the molecular weight of the interpolymer and/ or polyepoxide and the ultimate crosslink density and the chemical and physical properties desired.

A catalyst is not usually required for the crosslinking or curing reaction, but catalysts are often advantageously employed. Part of the uniqueness of the present compositions resides in their relatively stable pot life. The carboxamide-polyepoxide compositions have a long pot life, while the sulfonamide-polyepoxide compositions have a relatively shorter pot life. A mixture of the components is stable at ambient temperatures. When a fast rate of cure is desired, appropriate quantities of a catalyst or accelerator can be added. Typical catalysts are sodium hydroxide, stannous octoate, and 2,4,6-tri(dimethylamino methyl) phenol.

The temperatures necessary to cure the compositions can range from about 250 F. to about 450 F., prefera- 3 bly from about 300 F. to about 400 F. Curing of the amide-polyepoxide compositions is usually complete when heated within this preferred temperature range for about 30 minutes to about 2 hours.

4 EXAMPLE 4 Five grams of a 20 weight percent solution of a 15 percent acrylamide-SS percent butylacrylate copolymer dissolved in acetone was mixed with 0.4 gram of m-diiso- The novel amide-epoxide compositions of the prese 5 o enylbenzene diepoxide. The resulting solution was invention exhibit remarkable and unexpected properties cast as a film on steel panels and was baked at 0 R qmte dlfierent from any polym es of S 1m1 1ar comPosltlon for 1 hour. The resultant coating showed only slight attack known to the art. The compositions herein described are by rubbing for 1 minute with acetone useful in making varnishes, protective coatings, adhesives, films, and fibers. They are also useful for laminating glass EXAMPLE 5 and for encapsulating electronic components, and the like. A 5 gram portion f a 0 weight percent Solution f a The followmg examples are illustrative of the present 2 percent acrylamide go percent Styrene copolymer di invention, but are not to be construed as limiting the Solved in di th 1 f id was mixed with a Stoichi- W thefeofometric amount of m-diisopropenylbenzene diepoxide EXAMPLE 1 (0.26 g.). A film prepared by baking a coated steel panel at 300 F. for 1 hour, was hard, well adhered, and solvent A styrene-sulfonamlde copolymer was prepared by heatresistant mg a mlxture of: Similar results are obtained by replacing the epoxides Grams used in the foregoing examples with diglycidyl ether of Vi 1-b lf id 3 bisphenol A. Similar results are also obtained by replacing Styrene 12 the mterpolymers used 1n the foregoing examples with Acetone one of the following: an interpolymer of styrene-acrylx l 150 amide acrylonitrile, styrene diethylmaleate acryl- Azobisisobutyronitrile 0.25 mide, or vinyl pyrrolidone-acrylamide-ethyl acrylate.

. 25 at 50 to 65 C. for 8 hours. At the end of this tlme, the EXAMPLE 6 copolymer was precipitated by pouring the mixture into A 01 was re aredb o1 merizin tha followin methyl alcohol. The conversion was 33 percent. Infrared p y P p yp y g analysis showed the presence of the sulfonamide group Grams in the solid polymer Ethenesulfonamide (CH CHSO NH 1.25 The p-vinylbeuzene sulfonamide was generally prepared Butyl acrylate according to the procedure described by Wiley et al., J. ethyl f l (anhydrous) Am. Chem. Soc. 75, 4519 1953 which reportedly pro- Azoblslsobiltymmmle duces. P-" Y sulfonqmlde- The monomer y The monomer solution was heated at 60-65 C. for about contain minor amounts oftheisomers. 35 12 hours. After cooling a clear, oily, viscous solution EXAMPLE 2 (21.2 gm.) was obtained. The product, by infra-red analysrs, showed a strong NH doublet at 2.95 1. and 3.05,u., grflm of the copolymer prfpal'ed Example 1 a strong ester. at 5.85-5.90u and 80 near 8.6,u. The mlxefl gram P m'dllsopl'oPenyl benzene ethenesulfonamide was prepared generally according to epoxide, 1n 4 grams of dimethyl sulfoxide as solvent. The 40 the Procedure described by Maflack in l Polymer resultant solution was spread as a layer on a bonderized Sci 23, 729 (1958) steel plate and dried and baked for 30 minutes at 350 F. Assuming one reactive NH group per sulfonamide the was obtained a shghtly yellow, hard It was polymer had a calculated equivalent weight of about 535. acted by a 90 second rub with acetone' A mixture of 5 gms. of the polymer solution and 0.5 gm.

EXAM LE 3 of a diglycidyl ether of bisphenol A having an epoxide equivalent weight of 186-192 was prepared. A coating on A 30,We1ght pe rcent solutlon of a 30 welght Percent a phosphatized metal panel was prepared and allowed to acrylamldeqo welght j f butyl acrylate air dry for 30 minutes. The film was not completely cured was prepared by polymerizing the monomers in dimethyl (soluble in acetone) but was not tacky. Curing of the film formamlde as f solvent 98 y PerOXlde as a cataat 300 F. for 30 minutes produced a hard, slightly hazy lyst. The reaction was carried out at C. The converfilm with excelle t gloss, adhesion and fiexural propersion was 100 percent. ties, a pencil hardness of 6H to 9H and the film was unaf- In each of a series of experiments, 10 grams of the fected byaZminute rub with acetone.

TABLE 1 Run Bakin Temp.,

No. Diepoxide, gm. time (hr. F. Remarks 1 1.78 g. of (Unox 201) 3,4-epoxy 6- 1 350 Good film; 60 second acetone rub methyl cyclohexyl methyl-3,4- shows hazing and softening of figtgya-ttimethyl cyelohexane oarbaked film.

2- 0.89 g. (Unbx 206) vinyl cyelohexene 1 350 Good film; has less solvent resistance diox e. than Run 1. 3 1.05 g. (Unox 207) dieyelopentadiene 1 350 Do.

diepoxide.

4 (Unox 269) dipentenedioxide (1.07 g.). 1 400 Good film; 60 second acetone rub results in slight hazing and softening of film.

5 m-Dlvinylbenzene diepoxide (1.02g.) 300 Do.

6 m-Diisopropenyl benzene diepoxide 1 300 Hard film; 60 second acetone rub (1.21 g). results in hazing and very slight softening of film.

solution of the copolymer was mixed with a stoichiometric We claim:

amount of a diepoxide of a kind as stated in the following Table 1. The resulting solution was applied to steel panels, was dried and the film was baked for 1 hour at a tempera- 1. A crosslinkable resin composition comprising (1) an interpolymer having pendant amide groups, said interpolymer obtained by polymerizing from about 15 to about ture as shown in said table with results as shown therein. 30 percent by weight of an amide monomer selected from the group consisting of vinyl aromatic monoand disulfonamides, vinyl aliphatic sulfonamides, acrylamide, methacrylamide and mixtures thereof and corresponding- 1y from about 85 to about 70 percent by weight of at least one other copolymerizable monomer having no epoxide reactive sites, and (2) a polyepoxide having more than one oxirane group per molecule, said polyepoxide added in an amount corresponding to at least 0.1 equivalent of epoxide per each amide group of the interpolymer.

2. A composition as claimed in claim 1 wherein said interpolymer is a copolymer of butyl acrylate and acrylamide.

3. A composition as claimed in claim 2 wherein the polyepoxide is dipentene diepoxide, divinyl benzene diepoxide or a diglycidyl ether of bisphenol A.

4. A composition as claimed in claim 1 wherein the interpolymer is a copolymer of styrene and p-vinylbenzene sulfonamide.

5. A composition as claimed in claim 1 wherein the interpolymer is a copolymer of butyl acrylate and ethenesulfonamide.

6. A composition as claimed in claim 1 wherein the 6 amount of the polyepoxide ranges from 0.1 to 2 equivalents of epoxide per amide group.

7. A composition as claimed in claim 1 wherein the vinyl aliphatic sulfonamide monomer is ethenesulfonamide.

8. A composition as claimed in claim 1 wherein the vinyl aromatic sulfonamide is p-vinylbenzene sulfonamide.

9. An article comprising the heat cured composition of claim 1.

References Cited SAMUEL H. BLECH, Primary Examiner PAUL LIEBERMAN, Assistant Examiner US. Cl. X.R. 

